title: Graphene nucleation on transition metal surface: structure transformation and role of the metal step edge.
abstract: The nucleation of graphene on a transition metal surface, either on a terrace or near a step edge, is systematically explored using density functional theory calculations and applying the two-dimensional (2D) crystal nucleation theory. Careful optimization of the supported carbon clusters, C(N) (with size N ranging from 1 to 24), on the Ni(111) surface indicates a ground state structure transformation from a one-dimensional C chain to a 2D sp(2) C network at N ≈ 10-12. Furthermore, the crucial parameters controlling graphene growth on the metal surface, nucleation barrier, nucleus size, and nucleation rate on a terrace or near a step edge are calculated. In agreement with numerous experimental observations, our analysis shows that graphene nucleation near a metal step edge is superior to that on a terrace. On the basis of our analysis, we propose the use of graphene seeds to synthesize high-quality graphene in large area.
authors.affiliation: Institute of Textiles and Clothing, Hong Kong Polytechnic University, Hong Kong, People's Republic of China.
authors.forename: Junfeng
authors.initials: J
authors.lastname: Gao
authors.forename: Joanne
authors.initials: J
authors.lastname: Yip
authors.forename: Jijun
authors.initials: J
authors.lastname: Zhao
authors.forename: Boris I
authors.initials: BI
authors.lastname: Yakobson
authors.forename: Feng
authors.initials: F
authors.lastname: Ding
mesh_terms: D006108:Graphite / Q000737:chemistry*; D015394:Molecular Structure; D011789:Quantum Theory; D013499:Surface Properties; D028561:Transition Elements / Q000737:chemistry*
chemical_list: D028561:Transition Elements; D006108:Graphite